Objective: To report our day-to day experience with the long-term use of octreotide LAR in the treatment of acromegaly.
Patients and methods: Patients with acromegaly managed between 2003 and 2012 with octreotide LAR for a median of 27 months (interquartile ranges 12-60) and who had not received radiation therapy or concomitant treatment with cabergoline were retrospectively evaluated. Both primarily treated patients (n = 33) and patients who received octreotide after failed pituitary surgery (adjunctive treatment, n = 124) were included. Full biochemical response was defined as the achievement of a GH <2.5 ng/mL and an IGF-1 <1.2 times the upper limit of normal (× ULN); we also evaluated efficacy using a GH cut off of <1 ng/mL.
Results: Over 60% of the patients achieved a GH of <2.5 ng/mL. The combined GH (<2.5 ng/mL) and IGF-1 (<1.2 × ULN) target was achieved by 35.5 and 33.6% of the patients treated primarily and adjunctively, respectively; these figures dropped to 22.6 and 23% when using a GH target of <1 ng/mL. All patients reported a significant improvement in acromegalic symptoms. Lower pretreatment GH and IGF-1 levels were both associated with a higher probability of achieving the composite biochemical target.
Conclusion: Currently recommended GH and IGF-1 targets are reached by <36% of patients treated with octreotide LAR in a day-to day practice context. Nevertheless, in most instances a clinical benefit and an improvement in biochemical markers can be clearly documented.